Railway-traffic-controlling apparatus



ay R. A. MGCANN RAILWAY TRAFFIC CONTROLLING' APPARATUS Filed March 1,1924 Parenteel May 24,` 1927. Y

f f [U NJLITED Y 4or swissvntn; rijnnsnyninn, Assisivon To THE UNIONSWITCH e SlGNeLCOlVirANY, QF SWtSSvaI-a.trimm-VANI@ 1A CQRPORATIONRQNALD A- MQGANN,

or y rnNnsYLvAnIA.

, maan PASTE-.Nr oir-Flea.

Applcatonled March 1, 1924. `Serial No. 696,344.

vMy invention relatesr to railway traiiic controlling apparatus, and'particularly'tol apparatus of the typecomprising train caro ried-governing means controlled vby energy received from the trackway. "Moreparticularly my inventionrelates to the trackway portion of such`apparatus.

I will describe two forms of trackway apparatus embodying my invention,and will then point out the novel features thereof v1n claims. l

In the accompanying drawing,il `ig. l-is a diagrammatic view showing oneform y,of

trackway"apparatus embodying my invention.'` Fig. `Qis a view showing` amodified form flthe trackway apparatus shown vin Fig; 1 andalsoembodying my invention.

tlimilar'reference characters refer to similar parts in both views.Referring vlirst yto Fig. l, the reference characters il' and lfdesignate the track railsof a'stretch'of railway track, overv whichtraiiic :normally `moves in tl'ie'dire'ction indicated by the arrow.These track lrails are divided, by means of insulated joints 2, into aplurality of successive blocks, of'which only one'block A-C is shown inthe drawing. .This block 5r-C is divided by means of insulated joints 2into a forward track section B-C anda rear track 'section A#B. Each ofthe sections is providedwitli a track transformer designated by vthereference character T with a suitable exponent and having a secondarywinding 3 connected across the rails'adjacent the exit'end'of theassociated section. i An .impedance 5'is interposed between l.thesecondary' 3 of each track transformer T and one rail lwof'theassociated section in the usual manner. A track relay khere designatedby Vthe reference character R twith 4an eXponent corresponding to thelocation is connected Vacross the rails adjacent lthe entrance end ofyeach section. Y f f The primary lof .track transformer TC is'constantlysupplied with alternating current from terminals D and E, of a suitablesource of energy" notshownin the drawing.

LThe primaryA l oft'ransformer 'EB is supplied with alternating` currentover front but section B-C is unoccupied, relay RA is dei-.energized butvrelay Rfisenerg'ized, Vand when section B--Cf is `occupied relays RBand Re areboth cle-energized.

Located 'adjacent theentra'nce end of each block is apolar'ized linerelay designated-by the reference character G with an `rappropri-fy Kate eirponent.' Relay@C is omitted from the drawingfor thesakeof'simplicityj Locatedlat; the entrance end of each block is Yatrackway signal designated by the referencevcharacter Swith anappropriateexpone'nt and' controlled by theassociatedrelay'G. Y-Eachsignal as here shown i'sa threeposition semaphore signal capable ofdisplaying a proceed, a: caution ora 'stopindication. The control 'of'these'tsignals' forms no part; of my present invention andfis omittedfrom the drawing' for the saleof simplicity. F or present purposes itissulficient to state that each signal S is so controlled by itsassociated relay G that when the'corresponding block is occupiechthes'ignal indicates stop; when the corresponding block'is unoccupied`but'the block'next in advance'is occupied, the signal indicates caution,and when 'the vcorresponding'block and the nent block in advance areboth unoccupied the signal indicates proceed.

Associated ,with signal SC 'are a pole changer PC and a circuitcontroller KC', the functions of which will be descr-ibed'in ldetailhereinafter.

fplRelayGA comprises two windings ll and 12,'of which Iwinding l2 is'constantly supplied with alternating current from `ter minals'D and E.1Winding ll of this relay is supplied with alternating current of onerelative polarity when signal SC indicates caution or proceed, and withalternating current of theother relative polarity when signalmSCindicates stop, over a circuit passing from terminal D, through polechanger PC, wireV I6, frontl contact 17 of track 'relay RB, wire`18,'front contact '-19 of track relay RA, wire 20, winding l1 ofrelayGA, 'wire 21, and pole changerPC b'ack'to terminal This-circuit isclosed only when relays RB and VARAy are energized, under which,conditionsrelay RA is suppliedwith current of one relativetpolarity,which I will hereinafter term normal relative polarity 7, when signal SQindicates proceed'or caution, and with alternating current of the'otherrelative -iponected across the rails at an intermediate point in thesection. Loop current is'supplied to each section from a looptransformer designated by the reference character L with an exponentcorresponding to the location. Primary winding 10 of loop transformer LBis connected .across wires 18 and 21, and is therefore in parallel withrelay GA. The secondary 9 of transformer LB is connected with impedances6 and 7 in section A-B. Section A-B is therefore constantly suppliedwith alternating loop current as long as relay RB is energized. Itv willalso beclear that the relative polarity of such` loop current will bethe same as the relative polarity of the current supplied to relay GA,that is7 the loop current will be of normal relative polarity whensignal SC indicates proceed or caution and will be of reverse relativepolarity when signal SC indicates stop. In similar manner the primary 10of transformer LC is connected across wires 16 and 21, and is ythereforeconstantly supplied with alternating current of one relative polarity orthe other depending on the condition of signal SC. Section B-C isprovided with one local circuit which passes from secondary 9 oftransformer LC, through wire 28, circuit controller KC operated bysignal SC, wire 27, impedance 7 in section B-C, through both rails ofthe section in parallel to impedance 6 and wire 26 back to transformerLC. This circuit is closed only when signal SC indicates proceed orcaution. Under these circumstances therefore loop current of normalrelative polarity is supplied to section B-C throughout the length ofthe section. A second loop circuit is provided for section B-C overwhich current flows from secondary 9 of transformer LC, through wire 28,circuit controller KC controlled by signal SC, wire 29, impedance 8 insection B--G, through the rails of the section in parallel to impedance6, and Wire 26 back to secondary 9 of transformer LC. This circuit isclosed only when signal SC indicates stop, but under this condition thecurrent supplied by transformer LC is of reverse relative polarity, andloop current of reverse relative polarity is therefore supplied tosection B- C between impedances 6 and 8.

rIhe trackway apparatus herein shown and described is capable ofco-operation with train carried governingvmeans so that when the trainoccupies a stretch of track which is supplied with track circuit currentand with loop current of normal relative polarity a proceed indicationis received on the train; when the train occupies a portion of trackwhich is supplied with track circuit current and with loop current ofreverse relative polarity a caution indication is received on the train;and when the train occupies a portion of track to which the supply ofeither track circuit current or loop current is interrupted the trainreceives a stop indication. It follows that both the loop current andthe track circuit current` may be considered as train governingcurrents.r

As shown in the drawing signal SC indicates proceed and block A-G visunoccupied. Relays RA and RB are both energized and current of normalrelative polarity is supplied to winding 11 of relay GA and to theprimary 10 of transformers LB and LC. Sections A--B and B-G are eachsupplied with track circuit current and with loop current of normalrelative. polarity throughout the lengths of the sections. If,

now, a train moving in the direction of the arrow enters block A C suchtrain will receive a proceed indication throi'ighoutV the block. Theoperation of the apparatus would be the same were signal SC at caution.

I will next assume that signal SC is at stop, as by the presence of atrain in the block to-the right of point C. Pole changer PC and circuitcontroller KC are reversed and current of reverse relative polarity issupplied to winding 11 of relay GA and to the primary-10 of each of theloop transformers LB and LC. Loop current of reverse relative polarityis therefore supplied to the rails of section A-B throughoutL theirlength, and to the rails of section B-G between impedances 6 and 8, butno loop current is supplied te section B-C between impedances S and 7.If a train enters block A-G .under these conditions it will receive acaution indication from point A to impedance 8 in section B-G and a stopindication from impedance 8 to point C.

In the modification illustrated in Fig. 2 the track relays R aresupplied with direct current from trackbatteries 13 connected across therails adjacent the exit ends of the sections.` The secondaryB of a tracktransformer is interposed between each track battery 13 and one rail 1Lof the associated section for supplying alternating train controllingcurrent to the section. Primary 4 of transformer TB is in this viewconstantly supplied with alternating current from terminals D and E.Relay GA is a direct current relay and is supplied with energy from asuitable source pf directfcurrent such asl a battery N over a circuitsimilar to the circuit for relay GA in Fig. l. Located at point B is anauxiliary relay J connected across wires 18 and 2l. This relay Visresponsive to reversals of the relative polarity of the current suppliedthereto. The polar contacts 32 and 37 of relay J controlr the relativepolarity of the current supplied to primary l() of transformer LB. Theloop circuit for section A-B is the same as in Fig. l. The primary l oftransformer LC is constantly supplied with alternating current fromterminals D and E. One loop circuit for section B-C passes fromsecondary 9 of transformer LC, through wire 40,

. circuit controller KC operated by signal SC,

wir al, impedance 6 in section BC, through both rails of the section inparallel to impedance 7, and wire Ll2 back to secondary 9 of transformerLC. This circuit is closed only when signal SC indicates proceed orcaution, under which condition section B-C is supplied with loop currentof normal relative Vpolarity throughout the length of the section. Asecond loop circuit is provided for section B-C over which current.flows from secondary 9a of transformer LC, through wire 4ta, impedance8 in section B-C, through both rails of the section in parallel toimpedance 6, wire 4l, circuit controller KC operated by signal SC andwire 43 back to secondary 9 of transformer LC. This circuit is closedonly when signal SC indicates stop vunder which conditions lsection B-Cis supplied with loop current of reverse relative polarity betweenimpedances G and 8. The operation of the trackway apparatus shown inFig. 2 when a train traverses the stretch is the same as that explainedin connection with Fig. lV and.

tions may be made therein within the scope of the appended claimswithout Ideparting from the spirit and scope of my invention. Havingthus described my invention, what I claim'is: l

l. In combination, a forward .and a rear section of railway track,traffic governing means for said rear section Vincluding a polarizedrelay, a track relay for said rear section, a second track relay forsaid forward section, a pole changer; a circuit for said polarized relayincluding a front contact on said first. track relay, a front contact onsaid second track relay, said polechanger, and a winding of saidpolarized relay, and a transformer for supplying loop current to said,rear section'and having its primary winding connected in parallel withsaid polarized relay and the front contact of said first track relay.

2. In combination, a` forward and a rear section Vof railway track,tralic governing means for said' rear section including a polarizedrelay, a track relay for said rear section, a second track relay forsaid for ward section, a pole changer, a circuit for said polarizedrelay including a front contact on said firsttrack relay, a frontcontact on said second track relay, said pole changer, anda winding ofsaid polarized relay; a transformer for supplying loop current to saidrear section and having its primary winding connected in parallel withsaid polarized relay and the front `Contact y of said first track rela`anda second transformer for supplying loop current to said forwardsection and having a primary winding connected directly across said polechanger.

3. In combination, a block of railway track comprising a forward and arear section, traffic governing means for said block including a relay,a pole-changer controlled by traflic conditions in advance of saidforward section, and a circuit controlled by said pole-changer andincludingv three branches in multiple for supplying current to saidrelay and to the rails of said forward section and to the rails of saidrear section respectively. y

In testimony whereof I affix my signature.

RONALD A. MCCANN.

